Microray transmission line



19344 A. G. CLAVIER 1,971,90l

-MICRORAY TRANSMISSION LINE Filed Dec. 15, 1931 NvE N oR ANDR c. CLAVIER B Ye ATTRNEY Patented Aug. 28, 1934 PATENT' OFFICE' 1,9 7`1,901 MICRORAY TRANSMISSION, LNE Andre, G. Cl avier, GlenRidge, N. `J.`, assignor to International Communications Laboratories, Inc.;-Newark, N. J., a corporation of-` New York- I r i Application Decen ber 15, 19 31, Serial-No.v 81,147 e 'Claims. (Cl. 'na-44) i This invention relates to micro-raytransmission linesthat is, transmission lines for signaling systems in which :micro-ray's are used. 'These rays may be defined roughly as the electromagnetic waves thelength of 'which'lies between'the limits :of-100 centimeters and onecentimeter, although these limits 'may be exceeded in either direction. r In U. `S.Patent No. 1,928,408 I have disclosed apparatus for the transmission and reception of wavesin this range. In that application I' have also disclosed a transmission line between, the antenna and the micro-ray tube ;which consists of;.concentric conductors. It is desirable .that a u portionof: this line shall have agsmall characteristic impedance for maximum transfer of energy. v For this portion to have asmall characteristic impe'dance, it is necessary that the. ratio of the inside diameter of the external conductor to the outside diameter of the internal conductor L parallel `for their entire' length; :In the U.- S.-

patent above-referred to, it'is disclosed that a portion of the concentric transmission line may be a quarter-.wave'length longto act as a transformer and permit the internal impedance of the tube to matchthe impedance of theradiating system; This quarter-wave length section is most Conveniently connected directly to the leads from the oscillatingelectrode. a

' The object of this invention is to provide means for connecting the leads from the oscillating electrode to the concentric 'conductors'in such a mannerthat the leads may be parallel, the cencentric transmission line may have a lowchara'cteristio impedance,- and also' the dimensionspofthe external concentric conductor may be kept' small.

. In the drawing, r Fig; 1 is a diagrammatical sketch, partly in section, of 'a micro-ray tube, with the leads therefrom connected to two concentric conductors and the concentric conductors connected to a radiating system; and Fig; 2 is a diagrammatical sketchshowing how such 'asystem may be most' Conveniently 'con-.- nected to ,a thermocouple and galvanometer. InFig. '1 a micro-'ray tube 1 has acathodez, an oscillating electrode 3, and a refiecting electrode 4. In the tube 1- of the' type employed by 'applicant', it has been found that the plate ,or reflecting electrode '4 repels the electrons `projected toward it from the cathode 2, and these ,repelled ele trons .the ends of the oscillating electrode'.

set up difierences of potential along the length of the' grid or 'oscillating electrode 3. These differences of potential', in turn, cause a variation in i the electronic discharge taking place'between the cathode 2 and the plate 4 and thus produce oscillations in the tube 1. As the action of the plate 4 is analogous to the' phenomena of reflection, it

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has seemed desirable to term the plate the re fi'ecting electrode, andin view of the difierences of potential set -upalong the' length of the grid' 3; it has seemed desirable to term this element the oscillating electrode. Leads 5,'6 are connected to As above stated, distributed potential difference is set up along' the length of theoscillating 'electrode 3, and as the ends ofthis electrode constitute points of maximum'potential difference, it'is obviously desirable, in order to transfer to'the transmission line the high frequency E.: M. F. 'thus built up, to

connect theleads' and 6 to the ends oithis electrode. A concentric tra'nmisSion' line,- consisting' of an outer cylindrical'conductor 7 andan inner 'cylindrical' conductor '8, are shown conneoted to the-'leads 5, 6.- The lead 5 is con nected to a point 9 on the outer conductor andthe lead 6 is connected'toa point 10 on the inner conductor exactly opposite point 9.' That is, the points 9 and 10 li e on a linewhich dividesthe two' conductors into tw'o equal sections.` i The connections to these conductors may be made by` drilling a small hole` in each of them; inserting an end of the 'lead wire in the hole, and securing ittherein with s'o'lder. In order tomake 'this connection more easily, an extra thick'ness 'of metal can be fxed at points`9 and 10, as shown in the drawing, the first 'one outside the outer tube and the other one'in'side the inner tube, without introducing any'electrical disturbance in the transmission system. The requirement that the leads connecting the tube and the concentric transmission line be kept parallel is thus fulfilled by thetype of connection above described.

In Fig. 2 a concentric transmission line section 11 is shown adjacent a concentric transmission line section 14 having a larger cross-section. As the 'radius of the outer 'conductor in the section 11 is less than the' radius of the outer conductor in the section 14, it is evidently impossible to' makethe same type of connection betweenthese two transmission line sections as was made between the oscillating electrode 3 of the tube 1 and the' associated concentric transmission line. It has beenfound, however, that without changing the transmission characteristics of the transmissionline as a whole the 'outer conductor'of 5 `tor of the first transmssion line section is connected to; the remaining conductorof the second transmission line section. Accordingly, a socalled cross-over connection is made between the transmission line sections 11 and 14, that is, the

lead 12 connects the outer conductor of section 11 to the inner conductor of section 14, while the lead 13 connects the inner conductorof section 11 to the outer conductorof section 14.- y

This cross-over type ofyco'nnection, ofcourse,

might be used in connecting a' tube as 1 to an associated transmissicn line of the type shown in Fig. 1 whenever the radius of the outer conductor of the transmission line is' greater than the distance separating the leads as 5 and 6 connected to the opposite ends of the oscillating electrode 3 of .theatube ;1. 'It is to'be :noted that the leads 12 and.13.are'parall1in this` type of connection. This 'cross over type -o'f connection has a; furtheradvantage 'in 'that 'it permits the high fre quency current ;of a 'sectional transnission *line of ::the type` shown in Fig. 2. to be readily measured'bymeansdisclosed in U. S. Patents 1,921,117 and ,1,923,9,16. In these applications a Wavemeter and asfield strength measuring `device for ultra-'short wavesare respectively disclosed; ta thermocouple and atgalvanometer being used to measure `the Currents in -a concentric conductor. One of the .most convenient -methods of measuring.the,characteristics of a transmission line is to connect the ithermocouple to'one end of the concentric transmission'line: and "to connecta galvanometer between the outer "and inner conductors of .the line. The thermal E. M; F. set up by the thermocouple in accordance with the high 'frequency current of the transmission 'line Accordingly, the thermocouple T :is shown connected'to the'end of the transmission line section 14 by the leads zlandlfisin the same -manner that the tube 1 .in Fig..1;is shown-connected to the ;associated transmission line;

'For mechanical reasons it'isobviously desirable to be able to connect the galvanometerto the outer conductors of the transmission line sections 11 and *14, though-'otcoursezit is .necessary that the galvanometer be connected between the outer and inner conductors 'of the ttransmission line. In accordance with thearrangement of Fig. 2, this is readily accomplished because of the cross-over connection above mentioned; for, by connecting one side of the galvanometer to the outer conductor of the tra-nsmission line section 14, which-is connected to the inner conductor of the transmission line 'section 11,-and -connecting the-other 'end -of 'the galvanometer to the outer conductor of the transmission line section 1:1, which is connected to the inner conductor of the transmission 'line section l L-the required connections for-the galvanometer'can :be readily made; 1

After these connectionshave .been made; the thermocouple T sets up 'a thermal E'. pronortional to` the high .frequency current in the transmi'ssion' line, and this'E. MI'Frcauses a pro'- portional defiection of the' galvanmeter in a manner which 'is explained 'in *the above-*mentioned patents, with 'a "esulting .in'dication 'of the high frequency current in the transmission 1ine.-

It is evident that the galvanometer connections can be made at any point on the outer tubes of the transmisson line sections 11 and 14 without introducing any disturbancesin the propagation of the high frequency current.

What is claimed is:

1. In a micro-ray signalling system, a pair of parallel non-concentric leads and a transmission line consisting of concentric outer and inner conductors,one-leadbeing connected to a point on the outer conductor, and the other lead being connected to a pointon the inner conductor, both of saidpoints of connection lying in a diameter of the outer conductor but being on opposite sides of the center of said diameter.

' z'The'combination'of a micro vacuum tube havingan; oscillatng electrode-therein, leads parallel to one another connected to opposite ends of said oscillating electrode,"and a tran'smission line consisting` of concentric' otenand im'er conducto'rs, one lead 'being connected toa pointon the outer conductor and the other. lead being connected to .apoint on the inner conductor, both 'of said points of connection lying 'in'a diameter o'f the outer conductor but being on opposite sides of the center of said diameter. 3; A measuring 'system .for 'micro-rays cetnprising first and second sections of .a transmission line, each consisting of concentric outer an'd inner conductors, cross-over connections ?at 'adjacent ends of said sections between the outeran'd inner conductors threof, 'a thermocouple, coi nections 'between said thermocouple andfthe outer and inner conductorsof said second section at*points lying in a diameter of said outer con ductona galvanometer, and connections 'between said galvanometer and the outer"conductor`s e:

saidsections. r a

4. A 'micro-ray transmission line consisting of first andsecond sections, each comprising 'concentric outer and inner conductors, a pair of par allel leads, corresponding ends of said leads'bein'g connected to 'poirits'or' the outer andinner' con ductors *at adjacent ends of .said flrstand 'sec'- ond sections, the points of 'connection on the firstsection lying in a' diameter of thefouter con ductor thereof, one point lying' *at an extremity of said diameter and the other point atsubstantially. the center of said diameter, and the poin't of ?connection 'on said second section lying in s; diameter of the outer conductorthereot: buton thesam'e'side, of the center of said diameter, a thermocouple, and leads from` said' therm'ocouple connected `to the .inner and outer conductors' cf said second section 'at points of connetinlying in the diameter of said 'outer conductor.

5. In a'micro--ray signalling system, a 'pair of parallelnon-concentric leads, and atransmission line consisting of concentric outerand inner cnductors, one lead being connected to apoint o'n` the outerconductorand the other lead being con-` nected to a point on the inner conductor,- both of said points of connection lying in a diameter of the outer conductor. v r

6. In amicro-ray signalling system, a pair of parallel non-concentric leads and a transmission' line consisting of concentric outer and inner con ductors, one lead being connected to a point 'on the outer conductonand the other lead being connected'to a point on the inner conductor, both of said poin'ts of connection lying in a diameter of the outer conductor and on the same' side'of the I w I c l 150 center of sa d d ameter.

7. In a micro-ray signalling system, a pair of parallel leads and a pair of transmission line sections, each consisting of concentric outer and imner conductors, one of said sections having a'. larger cross-section than the other, corresponding ends of said leads being connected at adjacent ends of said sections to points on the outer and inner conductors thereof, the points of connection on each of said sections lying in a diameter of the outer conductors of said sections.

8. In a micro-ray signalling system, a pair of parallel leads and a pair of transmission line sections, each consisting of concentric outer and inner conductors, one of said sections having a larger cross-section than the other, corresponding ends of said leads being connected at adjacent ends of said sections to points on the outer and inner conductors of said sections, the points oi? connection on the smaller section lying in a diameter of the outer conductor thereof, one point being at an extfemity of said diameter and the other at substanti lly the center of. said diameter,

and the points of connection on the larger section ;lying in a diameter of the outer conductor thereof but on the same side of the center of said diameter.

9. In a micro-ray signalling system, the combination of a transmission line consisting of inner :and outer co-axial conductors, and a pair of non- :concentric parallel leads connected to the respective conductors at points thereon located in a plane containing the common axis of said conductors. V

10. In a micro-ray signalling system, the combination of a transm'ssion line consisting of inner and outer conductors so relatively positioned that the axes thereof lie in a plane which divides the respective conductors into two equal sections, and a pair of non-concentric parallel leads connected to the respective conductors at points thereon located in said plane.

ANDRE G. CLAVIER f 

